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This paper investigates the development of fabric materials using several blends of inherently fire-resistant (FR) fibers and various knitted structures. The samples are evaluated with respect to their performance and comfort-related properties. Inherently fire-resistant fibers, e.g., Nomex, Protex, carbon and FR viscose, were used to develop different structures of knitted fabrics. Cross-miss, cross-relief, and vertical tubular structures were knitted by using optimum fiber blend proportions and combinations of stitches. Several important aspects of the fabric samples were investigated, e.g., their physical, mechanical and serviceability performance. Thermo-physiological and tactile/touch-related comfort properties were evaluated in addition to flame resistance performance. An analysis of mechanical performance indicated that the knitted structure has a significant influence on the tensile strength, bursting strength and pilling resistance. The cross-relief structure proved to be the strongest followed by the cross-miss and vertical tubular structures. The FR station suits made from 70:30 Protex/Nomex exhibited the best combination of tensile and bursting strength; therefore, this material is recommended for making a stable and durable station suit. Interestingly, it was also concluded from the experimental study that knitted samples with a cross-relief structure exhibit the best fire-resistance performance. Fiber blends of 70:30 Protex/Nomex and 70:30 Nomex/carbon were found to be optimum in terms of overall performance. The best flame resistance was achieved with Nomex:carbon fiber blends. These results were confirmed with vertical flammability tests, TGA, DTGA and cone calorimetry analysis. The optimization of blend composition as well as knitting structure/architecture is a crucial finding toward designing the best FR station suit in terms of mechanical, dimensional, thermal, thermo-physiological and flame resistance performance. [ABSTRACT FROM AUTHOR]

For a sustainable environment and to tackle the pollution problem, industrial wastes can be used in concrete composite materials. This is especially beneficial in places prone to earth quack and lower temperature. In this study, five different types of waste fibres such as polyester waste, rubber waste, rock wool waste, glass fibre waste and coconut fibre waste were used as an additive in 0.5% 1%, and 1.5% by mass in concrete mix. Seismic performance related properties of the samples were examined through evaluation of compressive strength, flexural strength, impact strength, split tensile strength, and thermal conductivity. Results showed that, impact strength of the concrete significantly improved by the addition of fibre reinforcement in concrete. Split tensile strength and flexural strength were significantly reduced. Thermal conductivity was also influenced by addition of polymeric fibrous waste. Microscopic analysis was performed to examine the fractured surfaces. In order to get the optimum mix ratio, multi response optimization technique was used to determine the desired level of impact strength at an acceptable level of other properties. Rubber waste was found to be the most attractive option followed by coconut fibre waste for the seismic application of concrete. The significance and percentage contribution of each factor was obtained by Analysis of variance ANOVA (α = 0.05) and pie chart which showed that Factor A (waste fibre type) is the main contributor. Confirmatory test was done on optimized waste material and their percentage. The order preference similarity to ideal solution (TOPSIS) technique was used for developed samples to obtain solution (sample) which is closest to ideal as per given weightage and preference for the decision making. The confirmatory test gives satisfactory results with error of 6.68%. Cost of reference sample and waste rubber reinforced concrete sample was estimated, which showed that 8% higher volume was achieved with waste fibre reinforced concrete at approximately same cost as pure concrete. Concrete reinforced with recycled fibre content is potentially beneficial in terms of minimizing resource depletion and waste. The addition of polymeric fibre waste in concrete composite not only improves seismic performance related properties but also reduces the environmental pollution from waste material which has no other end use. [ABSTRACT FROM AUTHOR]